M. C. López de Azcona、R. Fort González、F. Mingarro Martín2002-03-01Materiales de Construccion
The water in Cibeles Fountain flows in a closed circuit and is replaced every 6 months. After this period of time, an increase in bicarbonate, sulfate, calcium and magnesium contents is registered in the water, as well as a slight increase in its acidity. This acidity, favored by atmospheric pollution, is the main cau…
Marisa M. Beppu、Cesar C. Santana2002-03-01Materials Research
The influence of the calcification solution on the mineralization of chitosan membranes was analysed. Two factors were studied: pH and chemical composition (excess of calcium or phosphate ions) of solutions. Substrates (membranes) of chitosan underwent mineralization by soaking in calcification solutions for 7 days at…
G. Thenoux、S. Vera2002-03-01Materiales de Construccion
Hexahydrated Magnesium Chloride or Bischofite is a salt. It has different properties that enable it to be useful as a chemical stabilizer of granular road surfaces: its capacity of absorbing and retaining humidity from its surrounding environment, increases water surface tension and decreases its vapor pressure. The o…
Francisca Puertas Maroto2002-03-01Materiales de Construccion
M. Castellote、M. C. Alonso、C. Andrade2002-03-01Materiales de Construccion
The most reliable method to determine the concentration of hydroxyl ions in the aqueous phase of hardened cementitious materials is the squeezing of concrete at high pressures. However, this method needs special equipment as well as a relatively high amount of sample to be carried out. In present research, the determi…
Elza F. Castro Vidaurre、Carlos A. Achete、Flávia da Cruz Gallo 等 6 位作者2002-03-01Materials Research
Low-temperature plasma treatment has been used in the last years as a useful tool to modify the surface properties of different materials, in special of polymers. In the present work low temperature plasma was used to treat the surface of asymmetric porous substrates of polysulfone (PSf) membranes. The main purpose of…
Diamond and Carbon-based Materials ResearchAdvanced Sensor and Energy Harvesting MaterialsSurface Modification and Superhydrophobicity
L. Melo、C.O. Avellaneda、R. Caram 等 5 位作者2002-03-01Materials Research
Thin solid films of Nb2O5 and Nb2O5:Li+ were prepared by the sol-gel process using the sonocatalytic method. The films reported here were prepared from a NbCl5 as precursor and butanol as solvent. Through the addition of lithium salt LiCF3SO3 to the precursor solution, films with different electrochemical performance…
Evandro Tolentino、Fernando S. Lameiras、Abdias M. Gomes 等 5 位作者2002-03-01Materials Research
We evaluated the "residual" thermal conductivity of Portland cement concretes (with characteristic compressive strength at 28 days, f ck, of 20 MPa and 50 MPa) at room temperature after heat-treating at 180 °C, 300 °C and 600 °C. The description of the geometry of the structure was carried out using mercury intrusion…
Fabiana Goia R. de Oliveira、Janaína Anadia O. de Campos、Almir Sales2002-03-01Materials Research
This paper reports on a study of the application of ultrasound waves in wood with the purpose of evaluating the latter's mechanical properties. The evaluation is based on the correlation between the speed of sound, modulus of elasticity and density. The speed of transmission is sensitive to the material's quality-dete…
A. F. Craievich2002-03-01Materials Research
Structural characterisations using the SAXS technique in a number of nanoheterogeneous materials and liquid solutions are reviewed. The studied systems are protein (lysozyme)/water solutions, colloidal ZnO particles/water sols, nanoporous NiO-based xerogels, hybrid organic-inorganic siloxane-PEG and PPG nanocomposites…
Iron oxide chemistry and applicationsX-ray Diffraction in CrystallographyEnzyme Structure and Function
M. Frías、M. I. Sánchez Rojas2002-03-01Materiales de Construccion
The commercial Portland cements contain minor elements in their chemical compositions. The presence of these elements has a direct incidence in different aspects: rheological behaviour, reaction kinetics, environmental, etc. Some of them also have a negative effect on the human health; so, chromium (Cr), nickel (Ni) a…
Edgar Dutra Zanotto2002-03-01Materials Research
M.L.C.P.da Silva、G.L.J.P. da Silva、D.N. Villela Filho2002-03-01Materials Research
This work describes two methods of preparation of hydrous tantalum phosphates and their characterization as ion exchangers. The hydrous metallic phosphate compounds were chemically and physically characterized by thermal gravimetric analysis, X-ray diffractometry and surface area measurements. By the first method, tan…
I.A. Santos、V.L. Arantes、D. Garcia 等 4 位作者2002-03-01Materials Research
Tungsten bonze structured lead barium niobate (Pb1-xBa xNb2O6) ferroelectric ceramics were prepared by the conventional mixed oxide method and their dielectric properties were carefully investigated. All studied samples presented elevated values of maximum dielectric constant (epsilon'm) and its corresponding temperat…
Mishu I. Zeidman、Paul Sawhney2002-03-01Textile Research Journal
The tensile and tear strengths and hence the durability of a cotton fabric are greatly influenced by the length and strength of cotton fibers in addition to the fabric structure. This is so because fiber length to a large extent determines yam strength, which ultimately contributes to fabric strength. Also, fiber leng…
Structural Analysis and OptimizationTextile materials and evaluations
Annelies Delabie、Kristine Pierloot、Marijke H. Groothaert 等 5 位作者2002-03-01European Journal of Inorganic Chemistry
Zeolites loaded with transition metal ions are promising heterogeneous catalysts. Knowledge about the location and structure of the metal centers is of paramount importance for the understanding of the catalytic potential of these materials. In this work, the spectroscopic studies of the coordination of CuII in zeolit…
Advanced Chemical Physics StudiesX-ray Diffraction in CrystallographyCatalytic Processes in Materials Science
William Parry、Mark D. Jasumback、Paula N. Wilson2002-03-01Economic Geology
The earliest alteration mineral zones in the porphyry Cu-Mo-Au ore deposit at Bingham, Utah, include the outermost propylitic and inner potassic alteration of igneous rocks. Innermost phyllic and intermediate argillic alteration is superimposed on propylitic and potassic alteration. Petrographic, X-ray diffraction, an…
Geochemistry and Geologic MappingGeological and Geochemical AnalysisClay minerals and soil interactions
Özer Göktepe、S.C. Harlock2002-03-01Textile Research Journal
In this work, a 3D computer aided designing (CAD) system is developed for solid modeling and visual simulation of warp knitted structures on Silicon Graphics workstations. In the first part, a three-dimensional cylindrical and uniform solid yarn model is developed, such that its central axis is a space curve, using no…
Textile materials and evaluations
Ping Jin、Gang Xu、Masato Tazawa 等 4 位作者2002-03-01Japanese Journal of Applied Physics
A novel window structure composed of VO 2 thermochromic film with TiO 2 antireflection (AR) coating was proposed. TiO 2 was chosen as the best AR candidatefor reasons that it is an AR material superior to the reported SiO 2 , and that it is capable to make the window multifunctional with excellent photocatalytic prope…
Transition Metal Oxide NanomaterialsTiO2 Photocatalysis and Solar CellsOptical Wireless Communication Technologies
G.G. Fuentes、E. Elizalde、F. Yubero 等 4 位作者2002-03-01Surface and Interface Analysis
Abstract Electron inelastic mean free paths (IMFP) have been estimated for Ti, TiC, TiN and TiO 2 for energies between 250 and 2000 eV. The IMFP values have been derived from the respective energy‐loss function (i.e. Im{−1/ ϵ }) on the basis of the model developed by Yubero and Tougaard for quantitative analysis using…
Electron and X-Ray Spectroscopy TechniquesX-ray Spectroscopy and Fluorescence AnalysisCorrosion Behavior and Inhibition